Originally published in The Weekly Packet, February 21, 2019
MDOT announces ‘preferred alternative’ for Falls Bridge
by Anne Berleant
The long journey to a decision on Falls Bridge is nearing an end based on a February 14 Maine Department of Transportation announcement.
“After a thorough investigation of options, including rehabilitation of the existing Falls Bridge, the preferred alternative is to replace the existing Falls Bridge superstructure with an enhanced girder bridge superstructure,” MDOT Project Manager Andrew Lathe stated in a press release. The enhancements refer to aesthetic features that will make the bridge unique among similar girder bridges.
The determination echoed what the bridge advisory committee and a dozen members of the public heard at a February 13 meeting, with Lathe joining in over speaker phone.
MDOT’s preferred alternative is not the final decision, Lathe told committee members, as state and federal environmental, archaeological and historical agencies will review MDOT’s determination before announcing the “selected alternative.”
Decisions on sidewalks, parking, hand rails and the like will be made as the engineering design progresses, with input from the bridge advisory committee. Meetings, open to the public, will be scheduled to address this, Lathe said.
“Certainly the economics had an impact [on the decision],” Brooklin Selectman and committee member Deborah Brewster said, “but I think the greatest part of the decision was to have the least impact.”
The estimated $8.9 million dollar cost is significantly cheaper than rehabilitation and, with a projected life span of 100 years, a girder bridge will last twice as long. Choosing this over the existing tied arch design provides “the safest structure for commuter and pedestrian use by removing the arch, lateral bracing and hangers; provided the lowest construction cost and construction risk; and provided the lowest cost for long-term inspection and maintenance,” according to the press release.
Specifics of the enhanced girder bridge are:
60-day accelerated construction;
No temporary bridge; traffic will be detoured through Routes 172 and 175;
In-water construction between November and March to lessen impact to natural resources;
Raised bridge level to accommodate sea level rise and improve travel conditions;
Rehabilitation of existing stone substructure.
The Bridge Advisory Committee met for 20 months, creating a design matrix that weighed the pros and cons of rehabilitation, replacement or an alternative bridge, taking into account impacts to the historical and architectural significance of the site, natural resources, cost, safety and travel, including emergency services, and local businesses, during the construction phase.
The 88-year-old bridge is the most direct route into South Blue Hill and Brooklin, with about 1,790 vehicle crossings per day, according to an MDOT traffic count in 2014, when bridge discussions began. A years-long delay occurred when archaeologically significant sites were discovered along the banks, as was the existence of the endangered Northern long-eared bat.
“Are you projecting an end of this project by the end of 2022?” committee member John Chapman asked upon hearing that the review process by consulting agencies could take months to complete.
Lathe said the projected completion date could be by the end of 2021 or early 2022.
“The process was long and thorough,” Schatz said. “As a group, I think a lot of us felt the [design] matrix spoke volumes to the least painful option.”